What does the term "blind spot" mean?

The term "blind spot" refers to areas around a vehicle that are not visible to the driver through their mirrors. These zones can be significant because they represent parts of the road that the driver cannot see without turning their head, potentially leading to unsafe driving conditions. Drivers should be aware of their vehicle’s blind spots to ensure they check these areas before changing lanes or merging. Awareness of blind spots is crucial for preventing collisions with vehicles or objects that may be present in those areas but not reflected in the side or rearview mirrors.

The other choices do not accurately define "blind spot." The area in front of the vehicle being always visible contradicts the concept, while a designated parking area or restrictions on entry for vehicles do not relate to the visual limitations experienced by drivers.